Transceivers of the type utilized in high speed data transmission typically require some type of analog front end that requires an analog driver for driving a transmission line for transmission of data thereto and an analog receiver for receiving data therefrom. Digital systems precede the analog transmitter for receiving and digitally processing input digital information, converting that digital information to analog information and then passing it through the analog transmitter. Similarly, the digital processing section also converts the received analog data to digital data for processing thereof. However, during manufacturing, especially with respect to very high speed transceiver designs such as those found in GBit/s transceivers, the operating characteristics of the analog section are important in order to meet the specifications of the various standards associated therewith.
In order to test devices during and after manufacture, various types of Automatic Test Equipment (ATE) have been utilized. However, analog ATE can be very expensive and slow. In some instances, the transceiver utilizes its transmission and receive paths in a loopback configuration to actually test the entire transmission path on a limited basis. As an alternative to utilizing an external ATE, some functionality of the testing operation can be built into the device. However, this sometimes requires the use of additional testing circuitry that adds to the cost, the area and the complexity of the device.